@book{402489, title = {\v C\'\i sla a po\v cetn\'\i\ v\'ykony}, series = {GDML\_Books}, publisher = {St\'atn\'\i\ nakladatelstv\'\i\ technick\'e literatury}, address = {Praha}, year = {1954}, language = {cs}, url = {http://dml.mathdoc.fr/item/402489} }
Čech, Eduard. Čísla a početní výkony. GDML_Books (1954), http://gdmltest.u-ga.fr/item/402489/